Adding CURRENT_API to Java/Kotlin Api Finder lint-check to stay up-to-date on each branch.

This is a fix for an error where the API is too low to run on tm-release.

Test: The current tests in checks/src/test work in gradle, will work on getting these to work on Soong in the future.
This may require a feature request since these tests are currently required to run in a Studio source tree (see b/162368644)

Change-Id: I75e758eac03f34dbe6df9fab6d45880f53dcfae8
diff --git a/checks/src/main/java/com/android/apifinder/ApiFinderIssueRegistry.kt b/checks/src/main/java/com/android/apifinder/ApiFinderIssueRegistry.kt
index f2f91e2..97c740f 100644
--- a/checks/src/main/java/com/android/apifinder/ApiFinderIssueRegistry.kt
+++ b/checks/src/main/java/com/android/apifinder/ApiFinderIssueRegistry.kt
@@ -1,12 +1,13 @@
 package com.android.apifinder
 
 import com.android.tools.lint.client.api.IssueRegistry
+import com.android.tools.lint.detector.api.CURRENT_API
 import com.google.auto.service.AutoService
 
 @AutoService(IssueRegistry::class)
 @Suppress("UnstableApiUsage")
 class ApiFinderIssueRegistry : IssueRegistry() {
     override val api: Int
-        get() = 7
+        get() = CURRENT_API
     override val issues = listOf(ApiFinderDetector.ISSUE)
 }